1. Field of the Invention
The invention relates to an exhaust-gas supply device of a turbine wheel of an exhaust-gas turbocharger.
2. Description of the Related Art
A supply device of said type is known from DE 10 2007 017 826 A1 in the form of a two-channel gas flow supply with a first inlet duct and at least one second inlet duct.
In so-called ignition sequence exhaust manifolds of internal combustion engines, such as in particular of spark-ignition engines, in each case the exhaust gas of those cylinders which are not in direct succession in the ignition sequence is merged. For example, in a four-cylinder engine, cylinder 1 and cylinder 4 and also cylinder 2 and cylinder 3 are merged in the case of a cylinder ignition sequence of 1-3-4-2. This firstly permits, especially in four-cylinder engines, a reduction in the mutual influencing of the cylinders during the charge exchange as a result of lower residual gas contents, which leads to increased fresh gas charging, and it is secondly possible by means of channel separation to increase the flow speed, as a result of which a greater proportion of kinetic energy is imparted to the turbine wheel of a turbocharger which is coupled to the internal combustion engine, and therefore the turbine power is increased considerably.
If the generic supply device is to be combined with an ignition sequence exhaust manifold of said type, however, there are resulting efficiency disadvantages for the charge exchange of the internal combustion engine, and also for the chronological sequence of exhaust-gas pulsations on the turbine wheel, as a result of a non-uniform loading if the volume and the length of the first channel or of one inlet duct are significantly greater than the volume and the length of the second channel or of the other inlet duct.